Quick Change Advice QB78 Bolt O-Ring?

I went through the same problem when I first got my Gauntlet, and I believe (99% sure) that they are similar. 









The FKM listed, is viton. So you want a viton(FKM) with a 75 hardness rating, i.d. 1.42, o.d. 3.68, w.d. 1.52 Silicone them up and use an arrow nock to slide them on.

I really wish someone had come forward and told me that originally, that is why I keep editing this post to get it right. I have been in your shoes, and it is a real pain. Good luck!

Very easy to change. Get your wife's seam ripper or a dental pick type tool and rip off the old ones. Smear the probe up with silicone grease or oil and slide the new ones on the skinny end. Go open a bottle of wine and slice off about a 1/2 inch of the cork and put between the breech and probe. Force the probe through the cork like you are loading a pellet. Pull the bolt back and throw the cork in your tool box. Now go drink the wine.

Does anyone know the name of an actual seller of these o rings on E bay? O rings for the QB 2 repeater are hard to find, no, impossible to find. I screwed mine up using a Gauntlet magazine in the Beeman repeater. The plastic on the magazine would barely touch the o rings enough to mess them up.I ordered some from Archer air guns but they sent me 8 of those little fat ones, which don't work.



Thanks,



Chupacabra

I have the ones from Archer for my Beeman 1085 (QB II) and they're fine so long as I use a single-shot tray. Once I change to using a rotary mag, whether the one that came with it or a Marauder, they get peeled off by the mag. I've had them end up getting jammed in the port, or jamming a pellet halfway down the barrel, or falling backwards into the action.

I'd very much like a source for some that stay in place.

I think the use of an O-ring there is a bad design, actually. A better solution would be if the bolt had a much wider, continuous narrow diameter where the O-rings go, and a rubber sleeve (tapered would be best) that fit into it. That would prevent the rolling back that the mag causes, it would seal as well or better, and somebody could charge a mint because nobody already has something like that.

Andy

I have Beeman Model 1085 QB II, and I messed up the 2 bolt probe o- rings by using a gauntlet magazine. If you use the gauntlet magazine, you have to modify the plastic holes the bolt probe goes in. There is a video on u tube on how to do it.

I had ordered those o rings from archer but they are much to large to use.

The black ones are in the kit and the original one from the Beeman Model 1085 QB II is the Gold one.

If anyone knows what size they are please let me know. I can't find any of them anyplace, but not knowing the size Im looking for does not help.



Thanks

I just ordered 33 o-rings from the O ring store. They are 4 cents each, minimum order of 33. They ship Fed Ex 2 day for 8 bucks.

---

$1.32

Sub-Total:


$7.99

FedEx Air Special (2 Day Air):


$9.31

Total:









Of course I am not 100% sure they are the right size. I am going off what Puma Carl posted. We will see and I will post one way or the other.





NOTICE!!!!! THE ABOVE O RINGS ARE THE WRONG SIZE. I RE-ORDERED

AND WILL POST LATER.



THIS IS MY NEW ORDER. 1.78mm X 3.68mm (NBR) Buna-N 70 Duro Metric O-Ring (N1.78X003.68)

The above o rings are the wrong size also. I am going to the Ace Hardware to get my old ones measured. Stay tuned.